Whether you’re driving a 500 horsepower sports car or a 96 horsepower economy hatchback, if the engine torque can’t reach the driving wheels through a complex gear maze, all the power under the hood of your car or truck is useless. Here is an introductory guide to help explain the mystery under the floor: what happens when you step on the accelerator.
Although front wheel drive can be found in classic models such as the 1929 cord, the vast majority of popular modern configurations are based on the 1959 Mini. Its creator Sir Alec isigonis placed the small engine laterally – laterally – under the hood, installed the transmission and differential in a device called the propeller shaft, and installed it under and behind the engine. Although some front drive vehicles use a longitudinal – front to rear – mounted transmission system, all components are still at the front. Because the front wheels must be able to steer and propel, they are connected to the axle half shaft through complex universal joints (called constant speed joints), which can transmit power smoothly in the case of severe articulation.
Automatic transmission (mistakenly called “automatic” by many drivers) ）The internal is the same as the standard manual transmission, but a series of servo devices controlled by computer are used to eliminate the need for manual shift. The easiest way to understand how an automatic transmission works is to imagine a robot sitting in the passenger seat to shift gears for you. Because they always shift at the correct speed and never grind gears, automatic transmissions have many advantages over standard manual transmissions. Increasing the convenience of use, prolonging the service life of the transmission, better fuel economy and higher acceleration are all expected by the automatic transmission.
This is the transmission that most people think of when they hear the word “automatic”, which is also the type of transmission in most cars. Planetary gear automatic transmission (PGAs) are generally not used in heavy vehicles. This is mainly because PGA relies on a series of hydraulically controlled clutches to transmit power; the clutches are easy to slip and cannot provide forward engagement of the standard transmission. This is very important for trucks because they rely on the back pressure of the engine to safely go downhill. If the truck is going downhill and the internal clutch of the transmission begins to slip, it can Energy will begin to accelerate uncontrollably under the action of gravity. This dangerous situation is called “out of control” and kills dozens, if not hundreds, of people every year.
The transmission was developed to allow the gear ratio between the vehicle engine and the wheels to change during deceleration or acceleration. Gear shifting is necessary to avoid not only excessive fatigue of the engine, but also to maintain its performance at the best speed. There are several types of manual and automatic transmissions used on trucks. For all kinds of transmissions, they are connected to the automobile engine through the clutch. The clutch decouples the transmission from the engine when the vehicle shifts gears.
There are two basic types of automobile transmission: asynchronous and synchronous. An asynchronous transmission has several gears and usually a reverse gear. In an asynchronous transmission, gears are shifted by engaging and disengaging the clutch. This type of transmission is very popular in large trucks, machinery and racing cars. Its advantages are simpler design, improved reliability and lower maintenance cost in the long run. For large trucks, there is an additional advantage, that is, they can greatly reduce the weight and carry more goods. On the other hand, the difference of synchronous transmission is that the gears are always meshed together in the gearbox, which requires less effort to shift. The clutch in a synchronous transmission is usually made of brass to match the speed of the gear before locking the shift.
There are two types of trucks. The first is the type of entertainment people use. These transmissions are very similar to automobile transmissions, with up to six gears, which can be automatic or manual. Large or heavy trucks have three types of transmissions: range, transfer, and range transfer. The range transmission is similar to the transmission used in small trucks, but it has a high and low gear division, allowing the same shift position to be reused in low and high gear modes. The transfer case transmission also adopts high and low transfer cases. It does not have high and low gears, but divides the gear into two, so that each position of the shift can be used for two gears (one high gear and one low gear). The split transmission is a combination of these two settings, allowing greater gear position and selection.
According to the data of progressive casualty insurance company, about 90% of the vehicles on the road are now automatic transmissions. However, some drivers prefer manual transmission and won’t choose anything else. Manual transmission has some obvious advantages, but there are several special disadvantages that urge consumers to choose automatic transmission.
The driver of a manual transmission must manually shift between forward gears, At the same time, use the pedal clutch to disengage the transmission from the engine during gear shift (put the transmission in neutral). For automatic transmission, once the driver changes to “drive” The car will do all the work. The driver needs to shift again only when he wants to stop, reverse, downshift on steep mountain roads or put the transmission in neutral. This makes driving the automatic transmission more convenient, especially for urban driving involving multiple starts and stops.
Driving with a standard transmission requires skill, especially in some cases. For example, even the most dedicated shift driver would like to have an automatic transmission when he meets a red light on a steep peak with heavy traffic. In order to move forward when the green light is on, she must avoid rolling backward, press the clutch and shift gears at the same time.
Disadvantages: learning the system
The standard gearbox is difficult to learn, and it may take several weeks for the driver to fully adapt to shifting. In addition, most driving courses in high schools and independent driving schools only teach automatic driving. A person who has never used a lever shift system must find someone to teach him.
A new car with a manual transmission costs about $800 to $900 less than an automatic transmission, as can be seen by comparing vehicle options on the websites of various manufacturers, including Ford and general motors.
A new car with a manual transmission costs about $800 to $900 less than an automatic transmission, as can be seen by comparing vehicle options on the websites of various manufacturers, including Ford and general motors.
Skilled manual transmission drivers have faster shift response and stronger control, which is a significant advantage in bad weather. According to Edmunds Com reported that the standard transmission provides more traction in snow, mud and wet conditions. If the car is trapped in the snow, it will be easier for the driver to shake out when he can control the transmission with the shift lever.
According to slate Com reported that by 2007, the fuel saving rate per gallon was generally about one to two miles, mainly on the highway. J. Mike omotoso, an analyst at D. power and associates, said in 2008 that the difference in fuel consumption was “negligible” and pointed out that many vehicles equipped with automatic transmission actually achieve better fuel economy in cities than vehicles equipped with five speed manual transmission.
